Method for inducing proliferation of retinal stem cells

ABSTRACT

The present invention relates to a method for promoting the proliferation of retinal stem cells using IL-17B. IL-17B is put into a cell culture medium containing retinal stem cells to promote the proliferation and/or differentiation of retinal stem cells. The retinal stem cells can then be transplanted into the retina to promote the growth of the photoreceptor cells, the rods and the cones. Also IL-17B can be administered directly into the retina to promote the proliferation and/or differentiation of the retinal stem cells.

BACKGROUND OF THE INVENTION

[0001] Vision is one of the most important special senses in humans.Light enters the eye and impinges on photoreceptors of a specializedepithelium, the retina. The photoreceptors include rods and cones. Rodshave low thresholds for detecting light and operate best underconditions of reduced lighting (scoptic vision). However, rods neitherprovide well-defined visual images nor contribute to color vision.Cones, by contrast, are not as sensitive as rods to light and so operatebest under daylight conditions (photopic vision). Cones are responsiblefor high visual acuity and color vision.

[0002] Information processing within the retina is performed by retinalinterneurons, and the output signals are carried to the brain by theaxons of retinal ganglion cells. Fetal and adult retinal stem cells giverise to all the various cell types in the retina including a) the rodand the cone photoreceptors, b) the horizontal, bipolar, and amacrineinterneurons, c) the ganglion projection neurons, and d) the Muller gliacells.

[0003] Degenerative diseases of the retina often result in blindness dueto the destruction of the rods or cones. Retinal stem cell therapy hasbeen developed in which retinal stem cells are harvested from thepatient grown and expanded in culture and reintroduced into the retinain an attempt to promote regeneration of the rods and cones. Growthfactors that have been used in culture to promote proliferation of theretinal stem cells include a) transforming growth factor alpha (TGF-α)and epidermal growth factor (EGF), b) fibroblast growth factor (FGF), c)TGF-β 2 & 3, and d) sonic hedgehog (shh). While these growth factors areuseful, there is still a need to discover additional agents to promotethe proliferation and differentiation of retinal stem cells intophotoreceptor rods or cones.

DESCRIPTION OF THE INVENTION

[0004] The present invention fills this need by providing for a methodof promoting the proliferation of retinal stem cells comprising bringingIL-17B into contact with retinal stem cells. Retinal stem cells can begrown in culture into which IL-17B is added and re-implanted into apatient's retina to produce functioning rods and cones of the retina.Alternatively, the IL-17B can be administered directly into retina.

[0005] The teachings of all of the references cited in the presentspecification are incorporated in their entirety herein by reference.

Definitions

[0006] The term “effective amount” as used herein regarding theeffective amount of IL-17B administered in accordance with the presentinvention means an amount of IL-17B that causes proliferation of retinalstem cells. The effective amount of IL-17B or IL-17 to be administeredis from 0.1 μg to 100 μg of IL-17B or IL-17 per kilogram of body weightper day. More preferably, the effective amount is from 1 μg to 500 μg ofIL-17B or IL- 17 per kilogram of body weight. IL-17B should beadministered daily until the symptoms of neuropathy dissipate. If theretinal stem cells are grown in culture, the concentration of IL-17B inthe culture medium should be at least 100 ng/ml.

[0007] IL-17B (formerly called ‘Zcyto7’) and a method for making IL-17Bpolypeptides have been disclosed in International Patent Application No.PCT/US98/08212, Publication No. WO 98/49310.

Introduction

[0008] The present invention is based upon the discovery that IL-17B orIL-17 can induce the proliferation and/or differentiation of retinalstem cells. IL-17B can be used to treat many ocular disorders in whichretinal neurons have degenerated, such as macular degeneration andglaucoma. Age-related macular degeneration is the leading cause ofblindness in the United States. Currently, there is no satisfactorytreatment. In promoting the proliferation of retinal stem cells, one canadminister IL-17B directly into the retina or by a gene therapy modalityto stimulate the growth of endogenous stem cells. Secondly, retinal stemcells can be removed from the patient and IL-17B can be used tostimulate the growth of retinal stem cells in vitro, and then transplantthe stem cells back into the retina of the patient.

[0009] Those skilled in the art will recognize that the sequencesdisclosed in SEQ ID NOs: 1, and 2 represent a single allele of the humanIL-17B. One can clone allelic variants of these sequences by probingcDNA or genomic libraries from different individuals according tostandard procedures.

Modes of Administration

[0010] In general, pharmaceutical formulations will include an IL-17Bprotein in combination with a pharmaceutically acceptable vehicle, suchas saline, buffered saline, 5% dextrose in water or the like.Formulations may further include one or more excipients, preservatives,solubilizers, buffering agents, albumin to prevent protein loss on vialsurfaces, etc. Methods of formulation are well known in the art and aredisclosed, for example, in Remington: The Science and Practice ofPharmacy, Gennaro, ed., (Mack Publishing Co., Easton, Pa., 19th ed.,1995). In a culture medium. in which retinal stem cells are growing, theIL-17B should be present at a concentration of at least 100 ng/ml. Ifthe IL-17B is administered directly into the retina, the therapeuticdoses will generally be in the range of 0.1 to 100 μg/kg of patientweight, with the exact dose determined by the clinician according toaccepted standards determination of dose is within the level of ordinaryskill in the art. The proteins may be administered for acute treatment,over one week or less, often over a period of one to three days or maybe used in chronic treatment, over several months or years.

Nucleic Acid-Based Therapeutic Treatment

[0011] IL-17B can be also administered to a retinal stem cell by meansof gene therapy. In one embodiment, a gene encoding an IL-17Bpolypeptide is introduced in vivo in a viral vector. Such vectorsinclude an attenuated or defective DNA virus, such as but not limited toherpes simplex virus (HSV), papillomavirus, Epstein Barr virus (EBV),adenovirus, adeno-associated virus (AAV), and the like. Defectiveviruses, which entirely or almost entirely lack viral genes, arepreferred. A defective virus is not infective after introduction into acell. Use of defective viral vectors allows for administration to cellsin a specific, localized area, without concern that the vector caninfect other cells. Examples of particular vectors include, but are notlimited to, a defective herpes virus 1 (HSV1) vector [Kaplitt et al.,Molec. Cell. Neurosci. 2: 320-330 (1991)], an attenuated adenovirusvector, such as the vector described by Stratford-Perricaudet et al., J.Clin. Invest. 90:626-630 (1992), and a defective adeno-associated virusvector [Samulski et al., J. Virol., 61:3096-3101 (1987); Samulski et al.J. Virol., 63:3822-3828 (1989)].

[0012] In another embodiment, the gene can be introduced into a retinalstem cell by means of a retroviral vector, e.g., as described inAnderson et al., U.S. Pat. No. 5,399,346; Mann et al., Cell, 33:153(1983); Temin et al., U.S. Pat. No. 4,650,764; Temin et al., U.S. Pat.No. 4,980,289; Markowitz et al., J. Virol. 62:1120 (1988); Temin et al.,U.S. Pat. No. 5,124,263; International Patent Publication No. WO95/07358, published Mar. 16, 1995 by Dougherty et al. and Blood, 82:845(1993).

[0013] Alternatively, the vector can be introduced by lipofection invivo using liposomes. Synthetic cationic lipids can be used to prepareliposomes for in vivo transfection of a gene encoding a marker [Felgneret al., Proc. Natl. Acad. Sci. USA, 84:7413-7417 (1987); see Mackey etal., Proc. Natl. Acad. Sci. USA, 85:8027-8031 (1988)]. The use oflipofection to introduce exogenous genes into specific organs in vivohas certain practical advantages. Molecular targeting of liposomes tospecific cells represents one area of benefit. It is clear thatdirecting transfection to particular cells represents one area ofbenefit. It is clear that directing transfection to particular celltypes would be particularly advantageous in a tissue with cellularheterogeneity, such as the pancreas, liver, kidney, and brain. Lipidsmay be chemically coupled to other molecules for the purpose oftargeting. Targeted peptides, e.g., hormones or neurotransmitters, andproteins such as antibodies, or non-peptide molecules could be coupledto liposomes chemically.

[0014] It is possible to remove the retinal stem cells from the body andintroduce the vector as a naked DNA plasmid and then re-implant thetransformed cells into the body. Naked DNA vector for gene therapy canbe introduced into the desired host cells by methods known in the art,e.g., transfection, electroporation, microinjection, transduction, cellfusion, DEAE dextran, calcium phosphate precipitation, use of a gene gunor use of a DNA vector transporter [see, e.g., Wu et al., J. Biol.Chem., 267:963-967 (1992); Wu et al., J. Biol. Chem., 263:14621-14624(1988)].

EXAMPLE 1 Cloning of IL-17B

[0015] IL-17B was identified from expressed sequence tag (EST) 582069(SEQ ID NO: 3) by its homology to Interleukin-17. The EST582069 cDNAclone was obtained from the IMAGE™ consortium Lawrence LivermoreNational Laboratory through Genome Systems, Inc. The cDNA was suppliedas an agar stab containing E. coli transfected with the plasmid havingthe cDNA of interest and then streaked out on an LB 100 μg/ml ampicillinand 100 μg/ml methicillin plate. The cDNA insert in EST582069 wassequenced. The insert was determined to be 717 base pairs long with a180 amino acid open reading frame and a 22 amino acid signal peptide.

EXAMPLE 2 Construction of IL-17B Expression Vectors

[0016] A 473 bp IL-17B PCR DNA fragment was generated with 1 μl of adilution of the EST582069 plasmid prep of Example 2 and 20 picomoles(pm) of primer SEQ ID NO: 4 and 20 pm primer SEQ ID NO: 5. The digestedreaction mixture was electrophoresed on a 1% TBE gel; the DNA band wasexcised with a razor blade and the DNA was extracted from the gel withthe Qiaquick<< Gel Extraction Kit (Qiagen). The excised DNA wassubcloned into plasmid nfpzp9, which had been cut with Bam and Xho.Nfpzp9 is a mammalian cell expression vector comprising an expressioncassette containing the mouse metallothionein-1 promoter, a sequenceencoding the tissue plasminogen activator (TPA) leader, then multiplerestriction sites. These were followed by the human growth hormoneterminator, an E. coli origin of replication and a mammalian selectablemarker expression unit containing the SV40 promoter, enhancer and originof replication, a dihydrofolate reductase gene (DHFR) and the SV40terminator.

[0017] IL-17B was purified by means of affinity chromatography usinganti-IL-17B antibodies.

EXAMPLE 3 Cloning of Murine IL-17B

[0018] Mouse IL-17B was identified from an expressed sequence tag (EST)660242 (SEQ ID NO: 8). EST660242 cDNA clone was obtained from the IMAGEconsortium Lawrence Livermore National Laboratory through GenomeSystems, Inc. The cDNA was supplied as an agar stab containing E. colitransfected with the plasmid having the cDNA of interest and thenstreaked out on an LB 100 μg/ml ampicillin, 25 μg/ml methicillin plate.The cDNA insert in EST660242 was sequenced. The insert was determined tobe 785 base pairs with an open reading frame of 180 amino acids and aputative 20 amino acid signal peptide. The sequences are defined by SEQID NO: 7 and SEQ ID NO: 6.

EXAMPLE 4 Proliferation of Retinal Stem Cells in Culture

[0019] Retinal stem cells were obtained from the retina of E17-18 ratembryos and grown in culture. Preliminary results indicate that humanrecombinant IL-17B stimulates the growth of retinal stem cells. Thecells spread out on the substrate within one day, and the IL-17B-treatedcells appeared to proliferate more rapidly than the control cells. Weverified that IL-17B stimulated the proliferation of these cells byusing an antibody that recognizes a protein present in M-phase cells(phosphohistone3). We found many more cells labeled withphospho-histone3 antibody in the culture containing the IL-17B.

1 28 1 736 DNA Homo sapiens CDS (57)...(596) 1 gaattcggca cgaggaggcgggcagcagct gcaggctgac cttgcagctt ggcgga atg 59 Met 1 gac tgg cct cac aacctg ctg ttt ctt ctt acc att tcc atc ttc ctg 107 Asp Trp Pro His Asn LeuLeu Phe Leu Leu Thr Ile Ser Ile Phe Leu 5 10 15 ggg ctg ggc cag ccc aggagc ccc aaa agc aag agg aag ggg caa ggg 155 Gly Leu Gly Gln Pro Arg SerPro Lys Ser Lys Arg Lys Gly Gln Gly 20 25 30 cgg cct ggg ccc ctg gcc cctggc cct cac cag gtg cca ctg gac ctg 203 Arg Pro Gly Pro Leu Ala Pro GlyPro His Gln Val Pro Leu Asp Leu 35 40 45 gtg tca cgg atg aaa ccg tat gcccgc atg gag gag tat gag agg aac 251 Val Ser Arg Met Lys Pro Tyr Ala ArgMet Glu Glu Tyr Glu Arg Asn 50 55 60 65 atc gag gag atg gtg gcc cag ctgagg aac agc tca gag ctg gcc cag 299 Ile Glu Glu Met Val Ala Gln Leu ArgAsn Ser Ser Glu Leu Ala Gln 70 75 80 aga aag tgt gag gtc aac ttg cag ctgtgg atg tcc aac aag agg agc 347 Arg Lys Cys Glu Val Asn Leu Gln Leu TrpMet Ser Asn Lys Arg Ser 85 90 95 ctg tct ccc tgg ggc tac agc atc aac cacgac ccc agc cgt atc ccc 395 Leu Ser Pro Trp Gly Tyr Ser Ile Asn His AspPro Ser Arg Ile Pro 100 105 110 gtg gac ctg ccg gag gca cgg tgc ctg tgtctg ggc tgt gtg aac ccc 443 Val Asp Leu Pro Glu Ala Arg Cys Leu Cys LeuGly Cys Val Asn Pro 115 120 125 ttc acc atg cag gag gac cgc agc atg gtgagc gtg ccg gtg ttc agc 491 Phe Thr Met Gln Glu Asp Arg Ser Met Val SerVal Pro Val Phe Ser 130 135 140 145 cag gtt cct gtg cgc cgc cgc ctc tgcccg cca ccg ccc cgc aca ggg 539 Gln Val Pro Val Arg Arg Arg Leu Cys ProPro Pro Pro Arg Thr Gly 150 155 160 cct tgc cgc cag cgc gca gtc atg gagacc atc gct gtg ggc tgc acc 587 Pro Cys Arg Gln Arg Ala Val Met Glu ThrIle Ala Val Gly Cys Thr 165 170 175 tgc atc ttc tgaatcacct ggcccagaagccaggccagc agcccgagac 636 Cys Ile Phe 180 catcctcctt gcacctttgtgccaagaaag gcctatgaaa agtaaacact gacttttgaa 696 agccagaaaa aaaaaaaaaaaaaaaaattc ctgcggccgc 736 2 180 PRT Homo sapiens 2 Met Asp Trp Pro HisAsn Leu Leu Phe Leu Leu Thr Ile Ser Ile Phe 1 5 10 15 Leu Gly Leu GlyGln Pro Arg Ser Pro Lys Ser Lys Arg Lys Gly Gln 20 25 30 Gly Arg Pro GlyPro Leu Ala Pro Gly Pro His Gln Val Pro Leu Asp 35 40 45 Leu Val Ser ArgMet Lys Pro Tyr Ala Arg Met Glu Glu Tyr Glu Arg 50 55 60 Asn Ile Glu GluMet Val Ala Gln Leu Arg Asn Ser Ser Glu Leu Ala 65 70 75 80 Gln Arg LysCys Glu Val Asn Leu Gln Leu Trp Met Ser Asn Lys Arg 85 90 95 Ser Leu SerPro Trp Gly Tyr Ser Ile Asn His Asp Pro Ser Arg Ile 100 105 110 Pro ValAsp Leu Pro Glu Ala Arg Cys Leu Cys Leu Gly Cys Val Asn 115 120 125 ProPhe Thr Met Gln Glu Asp Arg Ser Met Val Ser Val Pro Val Phe 130 135 140Ser Gln Val Pro Val Arg Arg Arg Leu Cys Pro Pro Pro Pro Arg Thr 145 150155 160 Gly Pro Cys Arg Gln Arg Ala Val Met Glu Thr Ile Ala Val Gly Cys165 170 175 Thr Cys Ile Phe 180 3 397 DNA Homo sapiens variation 10 n =A, T, C, or G 3 aggcgggcan agctgcaggc tgaccttgca gcttggcgga atggactggcctcacaacct 60 gctgtttctt cttaccattt ccatcttcct ggggctgggc agccaggagccccaaaagca 120 agaggaaggg gcaagggcgg cctgggcccn tggcctggcc tcaccaggtgccactggacc 180 tggtgtcacg gatgaaaccg tatgcccgca tggaggagta tgagaggaacatcgaggaga 240 tggtggccca gctgaggaac agctcanaag ctggcccaga gaaagtgtgaggtcaacttg 300 cagctgtgga tgtccaacaa gaaggagcct gtctcccttg gggctacaagcatcaaccac 360 cgaccccagc cgtatccccg tgggaccttg ccgggac 397 4 18 DNAHomo sapiens 4 ttaccatttc catcttcc 18 5 18 DNA Homo sapiens 5 cccttcctcttgcttttg 18 6 692 DNA Mus musculus CDS (50)...(589) 6 ggggttcctggcgggtggca gctgcgggcc tgccgcctga cttggtggg atg gac tgg 58 Met Asp Trp 1ccg cac agc ctg ctc ttc ctc ctg gcc atc tcc atc ttc ctg gcg cca 106 ProHis Ser Leu Leu Phe Leu Leu Ala Ile Ser Ile Phe Leu Ala Pro 5 10 15 agccac ccc cgg aac acc aaa ggc aaa aga aaa ggg caa ggg agg ccc 154 Ser HisPro Arg Asn Thr Lys Gly Lys Arg Lys Gly Gln Gly Arg Pro 20 25 30 35 agtccc ttg gcc cct ggg cct cat cag gtg ccg ctg gac ctg gtg tct 202 Ser ProLeu Ala Pro Gly Pro His Gln Val Pro Leu Asp Leu Val Ser 40 45 50 cga gtaaag ccc tac gct cga atg gaa gag tat gag cgg aac ctt ggg 250 Arg Val LysPro Tyr Ala Arg Met Glu Glu Tyr Glu Arg Asn Leu Gly 55 60 65 gag atg gtggcc cag ctg agg aac agc tcc gag cca gcc aag aag aaa 298 Glu Met Val AlaGln Leu Arg Asn Ser Ser Glu Pro Ala Lys Lys Lys 70 75 80 tgt gaa gtc aatcta cag ctg tgg ttg tcc aac aag agg agc ctg tcc 346 Cys Glu Val Asn LeuGln Leu Trp Leu Ser Asn Lys Arg Ser Leu Ser 85 90 95 cca tgg ggc tac agcatc aac cac gac ccc agc cgc atc cct gcg gac 394 Pro Trp Gly Tyr Ser IleAsn His Asp Pro Ser Arg Ile Pro Ala Asp 100 105 110 115 ttg ccc gag gcgcgg tgc cta tgt ttg ggt tgc gtg aat ccc ttc acc 442 Leu Pro Glu Ala ArgCys Leu Cys Leu Gly Cys Val Asn Pro Phe Thr 120 125 130 atg cag gag gaccgt agc atg gtg agc gtg cca gtg ttc agc cag gtg 490 Met Gln Glu Asp ArgSer Met Val Ser Val Pro Val Phe Ser Gln Val 135 140 145 ccg gtg cgc cgccgc ctc tgt cct caa cct cct cgc cct ggg ccc tgc 538 Pro Val Arg Arg ArgLeu Cys Pro Gln Pro Pro Arg Pro Gly Pro Cys 150 155 160 cgc cag cgt gtcgtc atg gag acc atc gct gtg ggt tgc acc tgc atc 586 Arg Gln Arg Val ValMet Glu Thr Ile Ala Val Gly Cys Thr Cys Ile 165 170 175 ttc tgagccaaccaccaacccgg tggcctctgc aacaaccctc cctccctgca 639 cccactgtga ccctcaaggctgataaacag taaacgctgt tctttgtaaa gga 692 7 179 PRT Mus musculus 7 MetAsp Trp Pro His Ser Leu Leu Phe Leu Leu Ala Ile Ser Ile Phe 1 5 10 15Leu Ala Pro Ser His Pro Arg Asn Thr Lys Gly Lys Arg Lys Gly Gln 20 25 30Gly Arg Pro Ser Pro Leu Ala Pro Gly Pro His Gln Val Pro Leu Asp 35 40 45Leu Val Ser Arg Val Lys Pro Tyr Ala Arg Met Glu Glu Tyr Glu Arg 50 55 60Asn Leu Gly Glu Met Val Ala Gln Leu Arg Asn Ser Ser Glu Pro Ala 65 70 7580 Lys Lys Lys Cys Glu Val Asn Leu Gln Leu Trp Leu Ser Asn Lys Arg 85 9095 Ser Leu Ser Pro Trp Gly Tyr Ser Ile Asn His Asp Pro Ser Arg Ile 100105 110 Pro Ala Asp Leu Pro Glu Ala Arg Cys Leu Cys Leu Gly Cys Val Asn115 120 125 Pro Phe Thr Met Gln Glu Asp Arg Ser Met Val Ser Val Pro ValPhe 130 135 140 Ser Gln Val Pro Val Arg Arg Arg Leu Cys Pro Gln Pro ProArg Pro 145 150 155 160 Gly Pro Cys Arg Gln Arg Val Val Met Glu Thr IleAla Val Gly Cys 165 170 175 Thr Cys Ile 8 497 DNA Mus musculus 8ggggttcctg gcgggtggca gctgcgggcc tgccgcctga cttggtggga tggactggcc 60gcacagcctg ctcttcctcc tggccatctc catcttcctg gcgccaagcc acccccggaa 120caccaaaggc aaaagaaaag ggcaagggag gcccagtccc ttggcccctg ggctcatcag 180gtgccgctgg acctggtgtc tcgagtaaag ccctacgctc gaatggaaga gtatgagcgg 240aaccttgggg agatggtggc ccagctgagg aacagctccg agccagccaa gaagaaatgt 300gaagtcaatc tacagctgtg gttgtccaac aagaggagcc tgtccccatg gggctacagc 360atcaaccacg accccagccg catccctgcg gacttgcccg aggcgcggtg cctatgtttg 420ggttgcgtga atcccttcac catgcaggag gaccgtagca tggtgagcgt gccagtgttc 480agccaggtgc cggtgcg 497 9 160 PRT Homo sapiens 9 Gln Pro Arg Ser Pro LysSer Lys Arg Lys Gly Gln Gly Arg Pro Gly 1 5 10 15 Pro Leu Ala Pro GlyPro His Gln Val Pro Leu Asp Leu Val Ser Arg 20 25 30 Met Lys Pro Tyr AlaArg Met Glu Glu Tyr Glu Arg Asn Ile Glu Glu 35 40 45 Met Val Ala Gln LeuArg Asn Ser Ser Glu Leu Ala Gln Arg Lys Cys 50 55 60 Glu Val Asn Leu GlnLeu Trp Met Ser Asn Lys Arg Ser Leu Ser Pro 65 70 75 80 Trp Gly Tyr SerIle Asn His Asp Pro Ser Arg Ile Pro Val Asp Leu 85 90 95 Pro Glu Ala ArgCys Leu Cys Leu Gly Cys Val Asn Pro Phe Thr Met 100 105 110 Gln Glu AspArg Ser Met Val Ser Val Pro Val Phe Ser Gln Val Pro 115 120 125 Val ArgArg Arg Leu Cys Pro Pro Pro Pro Arg Thr Gly Pro Cys Arg 130 135 140 GlnArg Ala Val Met Glu Thr Ile Ala Val Gly Cys Thr Cys Ile Phe 145 150 155160 10 160 PRT Homo sapiens 10 Gln Pro Arg Ala Pro Lys Ser Lys Arg LysGly Gln Gly Arg Pro Gly 1 5 10 15 Pro Leu Ala Pro Gly Pro His Gln ValPro Leu Asp Leu Val Ser Arg 20 25 30 Met Lys Pro Tyr Ala Arg Met Glu GluTyr Glu Arg Asn Ile Glu Glu 35 40 45 Met Val Ala Gln Leu Arg Asn Ser SerGlu Leu Ala Gln Arg Lys Cys 50 55 60 Glu Val Asn Leu Gln Leu Trp Met SerAsn Lys Arg Ser Leu Ser Pro 65 70 75 80 Trp Gly Tyr Ser Ile Asn His AspPro Ser Arg Ile Pro Val Asp Leu 85 90 95 Pro Glu Ala Arg Cys Leu Cys LeuGly Cys Val Asn Pro Phe Thr Met 100 105 110 Gln Glu Asp Arg Ser Met ValSer Val Pro Val Phe Ser Gln Val Pro 115 120 125 Val Arg Arg Arg Leu CysPro Pro Pro Pro Arg Thr Gly Pro Cys Arg 130 135 140 Gln Arg Ala Val MetGlu Thr Ile Ala Val Gly Cys Thr Cys Ile Phe 145 150 155 160 11 160 PRTHomo sapiens 11 Gln Pro Arg Ser Pro Lys Ala Lys Arg Lys Gly Gln Gly ArgPro Gly 1 5 10 15 Pro Leu Ala Pro Gly Pro His Gln Val Pro Leu Asp LeuVal Ser Arg 20 25 30 Met Lys Pro Tyr Ala Arg Met Glu Glu Tyr Glu Arg AsnIle Glu Glu 35 40 45 Met Val Ala Gln Leu Arg Asn Ser Ser Glu Leu Ala GlnArg Lys Cys 50 55 60 Glu Val Asn Leu Gln Leu Trp Met Ser Asn Lys Arg SerLeu Ser Pro 65 70 75 80 Trp Gly Tyr Ser Ile Asn His Asp Pro Ser Arg IlePro Val Asp Leu 85 90 95 Pro Glu Ala Arg Cys Leu Cys Leu Gly Cys Val AsnPro Phe Thr Met 100 105 110 Gln Glu Asp Arg Ser Met Val Ser Val Pro ValPhe Ser Gln Val Pro 115 120 125 Val Arg Arg Arg Leu Cys Pro Pro Pro ProArg Thr Gly Pro Cys Arg 130 135 140 Gln Arg Ala Val Met Glu Thr Ile AlaVal Gly Cys Thr Cys Ile Phe 145 150 155 160 12 160 PRT Homo sapiens 12Gln Pro Arg Ser Pro Lys Ser Lys Arg Lys Gly Gln Gly Arg Pro Ala 1 5 1015 Pro Leu Ala Pro Gly Pro His Gln Val Pro Leu Asp Leu Val Ser Arg 20 2530 Met Lys Pro Tyr Ala Arg Met Glu Glu Tyr Glu Arg Asn Ile Glu Glu 35 4045 Met Val Ala Gln Leu Arg Asn Ser Ser Glu Leu Ala Gln Arg Lys Cys 50 5560 Glu Val Asn Leu Gln Leu Trp Met Ser Asn Lys Arg Ser Leu Ser Pro 65 7075 80 Trp Gly Tyr Ser Ile Asn His Asp Pro Ser Arg Ile Pro Val Asp Leu 8590 95 Pro Glu Ala Arg Cys Leu Cys Leu Gly Cys Val Asn Pro Phe Thr Met100 105 110 Gln Glu Asp Arg Ser Met Val Ser Val Pro Val Phe Ser Gln ValPro 115 120 125 Val Arg Arg Arg Leu Cys Pro Pro Pro Pro Arg Thr Gly ProCys Arg 130 135 140 Gln Arg Ala Val Met Glu Thr Ile Ala Val Gly Cys ThrCys Ile Phe 145 150 155 160 13 160 PRT Homo sapiens 13 Gln Pro Arg SerPro Lys Ser Lys Arg Lys Gly Gln Gly Arg Pro Gly 1 5 10 15 Pro Leu AlaPro Gly Pro His Gln Val Pro Leu Asp Leu Val Ala Arg 20 25 30 Met Lys ProTyr Ala Arg Met Glu Glu Tyr Glu Arg Asn Ile Glu Glu 35 40 45 Met Val AlaGln Leu Arg Asn Ser Ser Glu Leu Ala Gln Arg Lys Cys 50 55 60 Glu Val AsnLeu Gln Leu Trp Met Ser Asn Lys Arg Ser Leu Ser Pro 65 70 75 80 Trp GlyTyr Ser Ile Asn His Asp Pro Ser Arg Ile Pro Val Asp Leu 85 90 95 Pro GluAla Arg Cys Leu Cys Leu Gly Cys Val Asn Pro Phe Thr Met 100 105 110 GlnGlu Asp Arg Ser Met Val Ser Val Pro Val Phe Ser Gln Val Pro 115 120 125Val Arg Arg Arg Leu Cys Pro Pro Pro Pro Arg Thr Gly Pro Cys Arg 130 135140 Gln Arg Ala Val Met Glu Thr Ile Ala Val Gly Cys Thr Cys Ile Phe 145150 155 160 14 160 PRT Homo sapiens 14 Gln Pro Arg Ser Pro Lys Ser LysArg Lys Gly Gln Gly Arg Pro Gly 1 5 10 15 Pro Leu Ala Pro Gly Pro HisGln Val Pro Leu Asp Leu Val Ser Arg 20 25 30 Met Lys Pro Tyr Ala Arg MetGlu Glu Tyr Glu Arg Asn Ile Glu Glu 35 40 45 Met Val Ala Gln Leu Arg AsnSer Ser Glu Leu Ala Gln Arg Lys Cys 50 55 60 Glu Val Asn Leu Gln Leu TrpMet Ser Asn Lys Arg Ser Leu Ser Pro 65 70 75 80 Trp Gly Tyr Ser Ile AsnHis Asp Pro Ser Arg Ile Pro Val Asp Leu 85 90 95 Pro Glu Ala Arg Cys LeuCys Leu Gly Cys Val Asn Pro Phe Thr Met 100 105 110 Gln Glu Asp Arg SerMet Val Ser Val Pro Val Phe Ser Gln Val Pro 115 120 125 Val Arg Arg ArgLeu Cys Pro Pro Pro Pro Arg Thr Gly Pro Cys Arg 130 135 140 Gln Arg ValVal Met Glu Thr Ile Ala Val Gly Cys Thr Cys Ile Phe 145 150 155 160 15160 PRT Homo sapiens 15 Gln Pro Arg Ser Pro Lys Ser Lys Arg Lys Gly GlnGly Arg Pro Gly 1 5 10 15 Pro Leu Ala Pro Gly Pro His Gln Val Pro LeuAsp Leu Val Ser Arg 20 25 30 Met Lys Pro Tyr Ala Arg Met Glu Glu Tyr GluArg Asn Ile Glu Glu 35 40 45 Met Val Ala Gln Leu Arg Asn Ser Ser Glu LeuAla Gln Arg Lys Cys 50 55 60 Glu Val Asn Leu Gln Leu Trp Met Ser Asn LysArg Ser Leu Ser Pro 65 70 75 80 Trp Gly Tyr Ser Ile Asn His Asp Pro SerArg Ile Pro Val Asp Leu 85 90 95 Pro Glu Ala Arg Cys Leu Cys Leu Gly CysVal Asn Pro Phe Thr Met 100 105 110 Gln Glu Asp Arg Ser Met Val Ser ValPro Val Phe Ser Gln Val Pro 115 120 125 Val Arg Arg Arg Leu Cys Pro ProPro Pro Arg Thr Gly Pro Cys Arg 130 135 140 Gln Arg Leu Val Met Glu ThrIle Ala Val Gly Cys Thr Cys Ile Phe 145 150 155 160 16 160 PRT Homosapiens 16 Gln Pro Arg Ser Pro Lys Ser Lys Arg Lys Gly Gln Gly Arg ProGly 1 5 10 15 Pro Leu Ala Pro Gly Pro His Gln Val Pro Leu Asp Leu ValSer Arg 20 25 30 Met Lys Pro Tyr Ala Arg Met Glu Glu Tyr Glu Arg Asn IleGlu Glu 35 40 45 Met Val Ala Gln Leu Arg Asn Ser Ser Glu Leu Ala Gln ArgLys Cys 50 55 60 Glu Val Asn Leu Gln Leu Trp Met Ser Asn Lys Arg Ser LeuSer Pro 65 70 75 80 Trp Gly Tyr Ser Ile Asn His Asp Pro Ser Arg Ile ProVal Asp Leu 85 90 95 Pro Glu Ala Arg Cys Leu Cys Leu Gly Cys Val Asn ProPhe Thr Met 100 105 110 Gln Glu Asp Arg Ser Met Val Ser Val Pro Val PheSer Gln Val Pro 115 120 125 Val Arg Arg Arg Leu Cys Pro Pro Pro Pro ArgThr Gly Pro Cys Arg 130 135 140 Gln Arg Phe Val Met Glu Thr Ile Ala ValGly Cys Thr Cys Ile Phe 145 150 155 160 17 160 PRT Homo sapiens 17 GlnPro Arg Ser Pro Lys Ser Lys Arg Lys Gly Gln Gly Arg Pro Gly 1 5 10 15Pro Leu Ala Pro Gly Pro His Gln Val Pro Leu Asp Leu Val Gly Arg 20 25 30Met Lys Pro Tyr Ala Arg Met Glu Glu Tyr Glu Arg Asn Ile Glu Glu 35 40 45Met Val Ala Gln Leu Arg Asn Ser Ser Glu Leu Ala Gln Arg Lys Cys 50 55 60Glu Val Asn Leu Gln Leu Trp Met Ser Asn Lys Arg Ser Leu Ser Pro 65 70 7580 Trp Gly Tyr Ser Ile Asn His Asp Pro Ser Arg Ile Pro Val Asp Leu 85 9095 Pro Glu Ala Arg Cys Leu Cys Leu Gly Cys Val Asn Pro Phe Thr Met 100105 110 Gln Glu Asp Arg Ser Met Val Ser Val Pro Val Phe Ser Gln Val Pro115 120 125 Val Arg Arg Arg Leu Cys Pro Pro Pro Pro Arg Thr Gly Pro CysArg 130 135 140 Gln Arg Ala Val Met Glu Thr Ile Ala Val Gly Cys Thr CysIle Phe 145 150 155 160 18 160 PRT Homo sapiens 18 Gln Pro Arg Ser ProLys Ser Lys Arg Lys Gly Gln Gly Arg Pro Ser 1 5 10 15 Pro Leu Ala ProGly Pro His Gln Val Pro Leu Asp Leu Val Ser Arg 20 25 30 Met Lys Pro TyrAla Arg Met Glu Glu Tyr Glu Arg Asn Ile Glu Glu 35 40 45 Met Val Ala GlnLeu Arg Asn Ser Ser Glu Leu Ala Gln Arg Lys Cys 50 55 60 Glu Val Asn LeuGln Leu Trp Met Ser Asn Lys Arg Ser Leu Ser Pro 65 70 75 80 Trp Gly TyrSer Ile Asn His Asp Pro Ser Arg Ile Pro Val Asp Leu 85 90 95 Pro Glu AlaArg Cys Leu Cys Leu Gly Cys Val Asn Pro Phe Thr Met 100 105 110 Gln GluAsp Arg Ser Met Val Ser Val Pro Val Phe Ser Gln Val Pro 115 120 125 ValArg Arg Arg Leu Cys Pro Pro Pro Pro Arg Thr Gly Pro Cys Arg 130 135 140Gln Arg Ala Val Met Glu Thr Ile Ala Val Gly Cys Thr Cys Ile Phe 145 150155 160 19 160 PRT Homo sapiens 19 Gln Pro Arg Ser Pro Lys Val Lys ArgLys Gly Gln Gly Arg Pro Gly 1 5 10 15 Pro Leu Ala Pro Gly Pro His GlnVal Pro Leu Asp Leu Val Ser Arg 20 25 30 Met Lys Pro Tyr Ala Arg Met GluGlu Tyr Glu Arg Asn Ile Glu Glu 35 40 45 Met Val Ala Gln Leu Arg Asn SerSer Glu Leu Ala Gln Arg Lys Cys 50 55 60 Glu Val Asn Leu Gln Leu Trp MetSer Asn Lys Arg Ser Leu Ser Pro 65 70 75 80 Trp Gly Tyr Ser Ile Asn HisAsp Pro Ser Arg Ile Pro Val Asp Leu 85 90 95 Pro Glu Ala Arg Cys Leu CysLeu Gly Cys Val Asn Pro Phe Thr Met 100 105 110 Gln Glu Asp Arg Ser MetVal Ser Val Pro Val Phe Ser Gln Val Pro 115 120 125 Val Arg Arg Arg LeuCys Pro Pro Pro Pro Arg Thr Gly Pro Cys Arg 130 135 140 Gln Arg Ala ValMet Glu Thr Ile Ala Val Gly Cys Thr Cys Ile Phe 145 150 155 160 20 160PRT Homo sapiens 20 Gln Pro Arg Val Pro Lys Ser Lys Arg Lys Gly Gln GlyArg Pro Gly 1 5 10 15 Pro Leu Ala Pro Gly Pro His Gln Val Pro Leu AspLeu Val Ser Arg 20 25 30 Met Lys Pro Tyr Ala Arg Met Glu Glu Tyr Glu ArgAsn Ile Glu Glu 35 40 45 Met Val Ala Gln Leu Arg Asn Ser Ser Glu Leu AlaGln Arg Lys Cys 50 55 60 Glu Val Asn Leu Gln Leu Trp Met Ser Asn Lys ArgSer Leu Ser Pro 65 70 75 80 Trp Gly Tyr Ser Ile Asn His Asp Pro Ser ArgIle Pro Val Asp Leu 85 90 95 Pro Glu Ala Arg Cys Leu Cys Leu Gly Cys ValAsn Pro Phe Thr Met 100 105 110 Gln Glu Asp Arg Ser Met Val Ser Val ProVal Phe Ser Gln Val Pro 115 120 125 Val Arg Arg Arg Leu Cys Pro Pro ProPro Arg Thr Gly Pro Cys Arg 130 135 140 Gln Arg Ala Val Met Glu Thr IleAla Val Gly Cys Thr Cys Ile Phe 145 150 155 160 21 158 PRT Homo sapiens21 Arg Ser Pro Lys Ser Lys Arg Lys Gly Gln Gly Arg Pro Gly Pro Leu 1 510 15 Ala Pro Gly Pro His Gln Val Pro Leu Asp Leu Val Ser Arg Met Lys 2025 30 Pro Tyr Ala Arg Met Glu Glu Tyr Glu Arg Asn Ile Glu Glu Met Val 3540 45 Ala Gln Leu Arg Asn Ser Ser Glu Leu Ala Gln Arg Lys Cys Glu Val 5055 60 Asn Leu Gln Leu Trp Met Ser Asn Lys Arg Ser Leu Ser Pro Trp Gly 6570 75 80 Tyr Ser Ile Asn His Asp Pro Ser Arg Ile Pro Val Asp Leu Pro Glu85 90 95 Ala Arg Cys Leu Cys Leu Gly Cys Val Asn Pro Phe Thr Met Gln Glu100 105 110 Asp Arg Ser Met Val Ser Val Pro Val Phe Ser Gln Val Pro ValArg 115 120 125 Arg Arg Leu Cys Pro Pro Pro Pro Arg Thr Gly Pro Cys ArgGln Arg 130 135 140 Ala Val Met Glu Thr Ile Ala Val Gly Cys Thr Cys IlePhe 145 150 155 22 154 PRT Homo sapiens 22 Ser Lys Arg Lys Gly Gln GlyArg Pro Gly Pro Leu Ala Pro Gly Pro 1 5 10 15 His Gln Val Pro Leu AspLeu Val Ser Arg Met Lys Pro Tyr Ala Arg 20 25 30 Met Glu Glu Tyr Glu ArgAsn Ile Glu Glu Met Val Ala Gln Leu Arg 35 40 45 Asn Ser Ser Glu Leu AlaGln Arg Lys Cys Glu Val Asn Leu Gln Leu 50 55 60 Trp Met Ser Asn Lys ArgSer Leu Ser Pro Trp Gly Tyr Ser Ile Asn 65 70 75 80 His Asp Pro Ser ArgIle Pro Val Asp Leu Pro Glu Ala Arg Cys Leu 85 90 95 Cys Leu Gly Cys ValAsn Pro Phe Thr Met Gln Glu Asp Arg Ser Met 100 105 110 Val Ser Val ProVal Phe Ser Gln Val Pro Val Arg Arg Arg Leu Cys 115 120 125 Pro Pro ProPro Arg Thr Gly Pro Cys Arg Gln Arg Ala Val Met Glu 130 135 140 Thr IleAla Val Gly Cys Thr Cys Ile Phe 145 150 23 151 PRT Homo sapiens 23 LysGly Gln Gly Arg Pro Gly Pro Leu Ala Pro Gly Pro His Gln Val 1 5 10 15Pro Leu Asp Leu Val Ser Arg Met Lys Pro Tyr Ala Arg Met Glu Glu 20 25 30Tyr Glu Arg Asn Ile Glu Glu Met Val Ala Gln Leu Arg Asn Ser Ser 35 40 45Glu Leu Ala Gln Arg Lys Cys Glu Val Asn Leu Gln Leu Trp Met Ser 50 55 60Asn Lys Arg Ser Leu Ser Pro Trp Gly Tyr Ser Ile Asn His Asp Pro 65 70 7580 Ser Arg Ile Pro Val Asp Leu Pro Glu Ala Arg Cys Leu Cys Leu Gly 85 9095 Cys Val Asn Pro Phe Thr Met Gln Glu Asp Arg Ser Met Val Ser Val 100105 110 Pro Val Phe Ser Gln Val Pro Val Arg Arg Arg Leu Cys Pro Pro Pro115 120 125 Pro Arg Thr Gly Pro Cys Arg Gln Arg Ala Val Met Glu Thr IleAla 130 135 140 Val Gly Cys Thr Cys Ile Phe 145 150 24 160 PRT Homosapiens 24 His Pro Arg Asn Thr Lys Gly Lys Arg Lys Gly Gln Gly Arg ProSer 1 5 10 15 Pro Leu Ala Pro Gly Pro His Gln Val Pro Leu Asp Leu ValSer Arg 20 25 30 Val Lys Pro Tyr Ala Arg Met Glu Glu Tyr Glu Arg Asn LeuGly Glu 35 40 45 Met Val Ala Gln Leu Arg Asn Ser Ser Glu Pro Ala Lys LysLys Cys 50 55 60 Glu Val Asn Leu Gln Leu Trp Leu Ser Asn Lys Arg Ser LeuSer Pro 65 70 75 80 Trp Gly Tyr Ser Ile Asn His Asp Pro Ser Arg Ile ProAla Asp Leu 85 90 95 Pro Glu Ala Arg Cys Leu Cys Leu Gly Cys Val Asn ProPhe Thr Met 100 105 110 Gln Glu Asp Arg Ser Met Val Ser Val Pro Val PheSer Gln Val Pro 115 120 125 Val Arg Arg Arg Leu Cys Pro Gln Pro Pro ArgPro Gly Pro Cys Arg 130 135 140 Gln Arg Val Val Met Glu Thr Ile Ala ValGly Cys Thr Cys Ile Phe 145 150 155 160 25 158 PRT Homo sapiens 25 ArgAsn Thr Lys Gly Lys Arg Lys Gly Gln Gly Arg Pro Ser Pro Leu 1 5 10 15Ala Pro Gly Pro His Gln Val Pro Leu Asp Leu Val Ser Arg Val Lys 20 25 30Pro Tyr Ala Arg Met Glu Glu Tyr Glu Arg Asn Leu Gly Glu Met Val 35 40 45Ala Gln Leu Arg Asn Ser Ser Glu Pro Ala Lys Lys Lys Cys Glu Val 50 55 60Asn Leu Gln Leu Trp Leu Ser Asn Lys Arg Ser Leu Ser Pro Trp Gly 65 70 7580 Tyr Ser Ile Asn His Asp Pro Ser Arg Ile Pro Ala Asp Leu Pro Glu 85 9095 Ala Arg Cys Leu Cys Leu Gly Cys Val Asn Pro Phe Thr Met Gln Glu 100105 110 Asp Arg Ser Met Val Ser Val Pro Val Phe Ser Gln Val Pro Val Arg115 120 125 Arg Arg Leu Cys Pro Gln Pro Pro Arg Pro Gly Pro Cys Arg GlnArg 130 135 140 Val Val Met Glu Thr Ile Ala Val Gly Cys Thr Cys Ile Phe145 150 155 26 153 PRT Homo sapiens 26 Lys Arg Lys Gly Gln Gly Arg ProGly Pro Leu Ala Pro Gly Pro His 1 5 10 15 Gln Val Pro Leu Asp Leu ValSer Arg Met Lys Pro Tyr Ala Arg Met 20 25 30 Glu Glu Tyr Glu Arg Asn IleGlu Glu Met Val Ala Gln Leu Arg Asn 35 40 45 Ser Ser Glu Leu Ala Gln ArgLys Cys Glu Val Asn Leu Gln Leu Trp 50 55 60 Met Ser Asn Lys Arg Ser LeuSer Pro Trp Gly Tyr Ser Ile Asn His 65 70 75 80 Asp Pro Ser Arg Ile ProVal Asp Leu Pro Glu Ala Arg Cys Leu Cys 85 90 95 Leu Gly Cys Val Asn ProPhe Thr Met Gln Glu Asp Arg Ser Met Val 100 105 110 Ser Val Pro Val PheSer Gln Val Pro Val Arg Arg Arg Leu Cys Pro 115 120 125 Pro Pro Pro ArgThr Gly Pro Cys Arg Gln Arg Ala Val Met Glu Thr 130 135 140 Ile Ala ValGly Cys Thr Cys Ile Phe 145 150 27 128 PRT Homo sapiens 27 Met Lys ProTyr Ala Arg Met Glu Glu Tyr Glu Arg Asn Ile Glu Glu 1 5 10 15 Met ValAla Gln Leu Arg Asn Ser Ser Glu Leu Ala Gln Arg Lys Cys 20 25 30 Glu ValAsn Leu Gln Leu Trp Met Ser Asn Lys Arg Ser Leu Ser Pro 35 40 45 Trp GlyTyr Ser Ile Asn His Asp Pro Ser Arg Ile Pro Val Asp Leu 50 55 60 Pro GluAla Arg Cys Leu Cys Leu Gly Cys Val Asn Pro Phe Thr Met 65 70 75 80 GlnGlu Asp Arg Ser Met Val Ser Val Pro Val Phe Ser Gln Val Pro 85 90 95 ValArg Arg Arg Leu Cys Pro Pro Pro Pro Arg Thr Gly Pro Cys Arg 100 105 110Gln Arg Ala Val Met Glu Thr Ile Ala Val Gly Cys Thr Cys Ile Phe 115 120125 28 157 PRT Homo sapiens 28 Arg Ser Pro Lys Ser Lys Arg Lys Gly GlnGly Arg Pro Gly Pro Leu 1 5 10 15 Ala Pro Gly Pro His Gln Val Pro LeuAsp Leu Val Ser Arg Met Lys 20 25 30 Pro Tyr Ala Arg Met Glu Glu Tyr GluArg Asn Ile Glu Glu Met Val 35 40 45 Ala Gln Leu Arg Asn Ser Ser Glu LeuAla Gln Arg Lys Cys Glu Val 50 55 60 Asn Leu Gln Leu Trp Met Ser Asn LysArg Ser Leu Ser Pro Trp Gly 65 70 75 80 Tyr Ser Ile Asn His Asp Pro SerArg Ile Pro Val Asp Leu Pro Glu 85 90 95 Ala Arg Cys Leu Cys Leu Gly CysVal Asn Pro Phe Thr Met Gln Glu 100 105 110 Asp Arg Ser Met Val Ser ValPro Val Phe Ser Gln Val Pro Val Arg 115 120 125 Arg Arg Leu Cys Pro ProPro Pro Arg Thr Gly Pro Cys Arg Gln Arg 130 135 140 Ala Val Met Glu ThrIle Ala Val Gly Cys Thr Cys Ile 145 150 155

We claim:
 1. A method for inducing the proliferation and/ordifferentiation of retinal stem cells comprising bringing the retinalstem cells into contact with interleukin-17B (IL-17B).
 2. The method ofclaim 1 wherein the IL-17B polypeptide is selected from the groupconsisting of SEQ ID NOs: 2, 7, and 9-28.
 3. The method of claim 1wherein the retinal stem cells are grown in a culture medium.
 4. Themethod of claim 3 wherein the retinal stem cells are implanted into theretina of a mammal after the stems cells have come into contact withIL-17B.
 5. A method for inducing the proliferation and/ordifferentiation of retinal stem cells comprising administering IL-17Binto the retina.